Add packaging information to windowsdesktop transport package

eng/packaging.targets

@@ -35,6 +35,15 @@
     <!-- During NoBuild pack invocations, skip project reference build. Necessary for the IncludeProjectReferencesWithPackAttributeInPackage target. -->
     <BuildProjectReferences Condition="'$(NoBuild)' == 'true'">false</BuildProjectReferences>
   </PropertyGroup>
+
+  <!-- Flow these properties to consuming projects. Used by i.e. Microsoft.Internal.Runtime.WindowsDesktop.Transport. -->
+  <ItemDefinitionGroup>
+    <TargetPathWithTargetPlatformMoniker>
+      <IsPackable>true</IsPackable>
+      <PackageId>$(PackageId)</PackageId>
+      <PackageVersion>$(PackageVersion)</PackageVersion>
+    </TargetPathWithTargetPlatformMoniker>
+  </ItemDefinitionGroup>
 
   <PropertyGroup Condition="'$(PreReleaseVersionLabel)' == 'servicing'">
     <!-- In servicing, the live package is compared against the GA version in strict mode. -->

src/libraries/Microsoft.Internal.Runtime.WindowsDesktop.Transport/src/Microsoft.Internal.Runtime.WindowsDesktop.Transport.proj

@@ -1,4 +1,5 @@
 <Project Sdk="Microsoft.Build.NoTargets">
+
   <PropertyGroup>
     <TargetFramework>$(NetCoreAppCurrent)-windows</TargetFramework>
     <IsShipping>false</IsShipping>
@@ -10,6 +11,11 @@
     <PackageDescription>Internal transport package to provide windowsdesktop with the assemblies from dotnet/runtime that make up the Microsoft.WindowsDesktop.App shared framework.</PackageDescription>
     <!-- Reference elements are missing from the nuspec: https://github.com/NuGet/Home/issues/8684. -->
     <NoWarn>$(NoWarn);NU5131;NU5128</NoWarn>
+
+    <!-- Generate the transport props file -->
+    <BeforePack>$(BeforePack);GenerateTransportPropsFile</BeforePack>
+    <TransportPropsFileInputPath>$(MSBuildThisFileDirectory)build\$(MSBuildProjectName).props</TransportPropsFileInputPath>
+    <TransportPropsFileOutputPath>$(IntermediateOutputPath)$(MSBuildProjectName).props</TransportPropsFileOutputPath>
   </PropertyGroup>
 
   <ItemGroup>
@@ -21,5 +27,35 @@
                       Pack="true"
                       Private="true"
                       IncludeReferenceAssemblyInPackage="true" />
+
+    <PackageReference Include="Microsoft.DotNet.Build.Tasks.Templating" Version="$(MicrosoftDotNetBuildTasksTemplatingVersion)" />
   </ItemGroup>
+
+  <Target Name="GenerateTransportPropsFile"
+          DependsOnTargets="BuildOnlySettings;ResolveReferences"
+          Inputs="$(MSBuildThisFileFullPath);$(TransportPropsFileInputPath)"
+          Outputs="$(TransportPropsFileOutputPath)">
+    <ItemGroup>
+      <RuntimeWindowsDesktopPackageLibrary Include="@(ReferenceCopyLocalPaths->WithMetadataValue('ReferenceSourceTarget', 'ProjectReference')->WithMetadataValue('Extension', '.dll')->WithMetadataValue('Pack', 'true')->WithMetadataValue('IsPackable', 'true'))" />
+    </ItemGroup>
+
+    <PropertyGroup>
+      <RuntimeWindowsDesktopPackageLibraries>@(RuntimeWindowsDesktopPackageLibrary->'&lt;RuntimeWindowsDesktopPackageLibrary Include=&quot;%(Filename)%(Extension)&quot; PackageId=&quot;%(PackageId)&quot; PackageVersion=&quot;%(PackageVersion)&quot; /&gt;', '
+    ')</RuntimeWindowsDesktopPackageLibraries>
+    </PropertyGroup>
+
+    <ItemGroup>
+      <TransportPropsTemplateProperty Include="RuntimeWindowsDesktopPackageLibraries=$(RuntimeWindowsDesktopPackageLibraries)" />
+    </ItemGroup>
+
+    <GenerateFileFromTemplate
+      TemplateFile="$(TransportPropsFileInputPath)"
+      Properties="@(TransportPropsTemplateProperty)"
+      OutputPath="$(TransportPropsFileOutputPath)" />
+
+    <ItemGroup>
+      <None Include="$(TransportPropsFileOutputPath)" Pack="true" PackagePath="build/" />
+    </ItemGroup>
+  </Target>
+
 </Project>

src/libraries/Microsoft.Internal.Runtime.WindowsDesktop.Transport/src/build/Microsoft.Internal.Runtime.WindowsDesktop.Transport.props

@@ -0,0 +1,10 @@
+<Project>
+
+  <!-- The list of redistributed assemblies that also ship via out-of-band packages.
+       Includes the AssemblyName, PackageId and the PackageVersion:
+       <RuntimeWindowsDesktopPackageLibrary Include="" PackageId="" PackageVersion="" /> -->
+  <ItemGroup>
+    ${RuntimeWindowsDesktopPackageLibraries}
+  </ItemGroup>
+
+</Project>